/*
 * noise_radar.c -- BLE Device Radar Scanner module
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 *
 * v1.5: Restored from v1.3.  Uses BlueZ HCI inquiry (with RSSI when
 *       available, standard inquiry fallback) to discover BLE devices.
 *       Displays up to 4 nodes with RSSI-based heatmap coloring on a
 *       19-cell hexagonal grid.
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/socket.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/hci.h>
#include <bluetooth/hci_lib.h>
#include <linux/input.h>
#include "h2_ui.h"
#include "log_manager.h"

#define MAX_CELLS     19
#define SCAN_INTERVAL 8
#define RSSI_UNKNOWN  0

typedef struct {
    bdaddr_t addr;
    int8_t   rssi;
    uint8_t  active;
} ble_node_t;

static ble_node_t nodes[MAX_CELLS];
static int node_count;

static int scan_ble_nodes(int dev_id) {
    int max_rsp = 255, len = 8, flags = IREQ_CACHE_FLUSH;
    int num_rsp, new_count = 0;

    inquiry_info_with_rssi *rssi_info = NULL;
    num_rsp = hci_inquiry_with_rssi(dev_id, len, max_rsp, NULL, &rssi_info, flags);
    if (num_rsp >= 0) {
        for (int i = 0; i < num_rsp && new_count < MAX_CELLS; i++) {
            memcpy(&nodes[new_count].addr, &rssi_info[i].bdaddr, sizeof(bdaddr_t));
            nodes[new_count].rssi   = rssi_info[i].rssi;
            nodes[new_count].active = 1;
            new_count++;
        }
        free(rssi_info);
        return new_count;
    }

    inquiry_info *std_info = NULL;
    num_rsp = hci_inquiry(dev_id, len, max_rsp, NULL, &std_info, flags);
    if (num_rsp < 0) return num_rsp;
    for (int i = 0; i < num_rsp && new_count < MAX_CELLS; i++) {
        memcpy(&nodes[new_count].addr, &std_info[i].bdaddr, sizeof(bdaddr_t));
        nodes[new_count].rssi   = RSSI_UNKNOWN;
        nodes[new_count].active = 1;
        new_count++;
    }
    free(std_info);
    return new_count;
}

static lv_color_t rssi_to_color(int8_t rssi) {
    if (rssi == RSSI_UNKNOWN) return COLOR_MUTED;
    if (rssi > -50) return lv_color_make(50, 255, 100);
    if (rssi > -70) return COLOR_ACCENT;
    return COLOR_PRIMARY;
}

static void format_rssi(char *buf, size_t len, int8_t rssi) {
    if (rssi == RSSI_UNKNOWN) snprintf(buf, len, "rssi:?");
    else snprintf(buf, len, "rssi:%d", (int)rssi);
}

int main(void) {
    init_h2_graphics_runtime("BLE RADAR SCANNER");
    LOG_INF("radar module started");

    lv_obj_t *scr = lv_scr_act();

    lv_obj_t *title = lv_label_create(scr);
    lv_label_set_text(title, "BLE DEVICE RADAR");
    lv_obj_align(title, LV_ALIGN_TOP_MID, 0, 10);
    lv_obj_set_style_text_color(title, COLOR_PRIMARY, LV_PART_MAIN);

    lv_obj_t *console = lv_label_create(scr);
    lv_obj_set_width(console, 300);
    lv_label_set_long_mode(console, LV_LABEL_LONG_WRAP);
    lv_obj_align(console, LV_ALIGN_CENTER, 0, 20);

    lv_obj_t *hex_grid[MAX_CELLS];
    int start_x = 160, start_y = 120, spacing_x = 32, spacing_y = 28;
    int cell_count = 0;

    for (int r = -2; r <= 2; r++) {
        int max_c = 5 - abs(r);
        for (int c = 0; c < max_c; c++) {
            if (cell_count >= MAX_CELLS) break;
            hex_grid[cell_count] = lv_obj_create(scr);
            lv_obj_set_size(hex_grid[cell_count], 26, 26);
            lv_obj_set_style_radius(hex_grid[cell_count], LV_RADIUS_CIRCLE, LV_PART_MAIN);
            int px = start_x + (c * spacing_x) - ((max_c - 1) * spacing_x / 2);
            int py = start_y + (r * spacing_y);
            lv_obj_set_pos(hex_grid[cell_count], px - 13, py - 13);
            lv_obj_set_style_bg_color(hex_grid[cell_count], lv_color_make(30, 40, 50), LV_PART_MAIN);
            cell_count++;
        }
    }

    lv_obj_t *status = lv_label_create(scr);
    lv_obj_align(status, LV_ALIGN_BOTTOM_MID, 0, -8);
    lv_obj_set_style_text_color(status, COLOR_MUTED, LV_PART_MAIN);

    int dev_id = hci_get_route(NULL);
    int h_fd = (dev_id >= 0) ? hci_open_dev(dev_id) : -1;
    if (h_fd < 0) LOG_WRN("cannot open HCI device");
    int scan_tick = 0;

    int input_fd = open("/dev/input/event0", O_RDONLY | O_NONBLOCK);
    struct input_event ev;

    while (1) {
        lv_timer_handler();

        scan_tick++;
        if (scan_tick >= SCAN_INTERVAL && h_fd >= 0) {
            scan_tick = 0;
            memset(nodes, 0, sizeof(nodes));
            node_count = scan_ble_nodes(dev_id);

            for (int i = 0; i < cell_count; i++)
                lv_obj_set_style_bg_color(hex_grid[i], lv_color_make(30, 40, 50), LV_PART_MAIN);
            for (int i = 0; i < node_count && i < cell_count; i++)
                lv_obj_set_style_bg_color(hex_grid[i], rssi_to_color(nodes[i].rssi), LV_PART_MAIN);

            char addr_str[24], buf[256];
            buf[0] = '\0';
            for (int i = 0; i < node_count && i < 4; i++) {
                ba2str(&nodes[i].addr, addr_str);
                char rssi_str[16];
                format_rssi(rssi_str, sizeof(rssi_str), nodes[i].rssi);
                char line[64];
                snprintf(line, sizeof(line), "%s  %s\n", addr_str, rssi_str);
                strlcat(buf, line, sizeof(buf));
            }
            if (node_count == 0) snprintf(buf, sizeof(buf), "No BLE devices in range");
            lv_label_set_text(console, buf);

            char count_str[48];
            if (node_count > 0 && nodes[0].rssi == RSSI_UNKNOWN)
                snprintf(count_str, sizeof(count_str), "Scan: %d node(s) [RSSI n/a]", node_count);
            else
                snprintf(count_str, sizeof(count_str), "Scan: %d node(s)", node_count);
            lv_label_set_text(status, count_str);
        }

        if (input_fd >= 0 && read(input_fd, &ev, sizeof(struct input_event)) > 0) {
            if (ev.type == EV_KEY && ev.code == H2_KEY_BACK && ev.value == 1) break;
        }
        usleep(40000);
    }

    if (h_fd >= 0) close(h_fd);
    if (input_fd >= 0) close(input_fd);
    LOG_INF("radar module exited");
    return 0;
}